>> jim maceda in cairo, thank you. >>> in mexico a day of change and protests as a new president was sworn in. enrique pena nieto says his main goal is to reduce drug-related violence which killed more than 60,000 people in the six years felipe calderon was in office. vice president joe biden was among those who attended. outside there were clashes with police as thousands protested the election in which pena nieto won with only 38% of the vote. his victory represents the return of the party that long dominated mexican politics. >>> tonight people around the world are marking the 25th anniversary of world aids day, remembering the millions who have lost their lives and how far aids research and education has come in the past quarter century. in a live look now at the white house tonight a giant red ribbon hanging from the north portico reminding us all of the work still ahead to find a cure. >>> still heed ahead as "nbc nightly news" continues on this saturday evening, help wanted. thousands of open jobs at big brand name companies in this economy. how come they're having such a hard